Experimental Hematology Today – Serie

United States government. Defense Nuclear firms, Hoffman-LaRoche and Ciba-Geigy, and by Agency, Armed Forces Radiobiology Research In- the American firm, Travenol. stitute. SIEGMUNDJ. BAUM Furthermore, we greatly appreciate the gener- G. DAVID LEDNEY ous financial support by the Swiss pharmaceutical vi Xlll List of Contributors Part I Regulation of Stem Cell Proliferation L. G. Lajtha 1 Regulation of Stem Cell Proliferation 3 L. G. Lajtha and E. G. Wright Introduction 3 Experimental Evidence 3 Summary 7 References 7 Contents 2 Surface Antigens of Hemopoietic Stem Cells: The Expression of BAS, Thy-1, and H-2 Antigens on CFU-s 9 Ger van den Engh, Jim Russell, and Diane de Cicco Introduction 9 Materials and Methods 10 Results 11 Discussion 13 Summary 14 Acknowledgments 14 References 15 3 The Regulation of Hemopoiesis: Effect of Thymosin or Thymocytes in a Diffusion Chamber 17 S. J. Sharkis, A. Ahmed, L. L. Sensenbrenner, W. W. Jedrzejczak, A. L. Goldstein, and K. W. Sell Introduction 17 Materials and Methods 17 Results 18 Discussion 20 Summary 21 Acknowledgments 21 References 21 4 Anti-CFU-s Activity of Rabbit Anti- mouse Brain Serum: Mechanism of Action 23 Solomon S.Adler, Richard D. Kuznetsky, and Frank E. Trobaugh, Jr. Introduction 23 Materials and Methods 23 Results 26 Discussion 29 Summary 31 Acknowledgments 31 References 31 vii Contents Part II Ralph van Furth, Theo J. L. M. Goud, and Physiology of Committed Dick van Waarde Stem Cells 33 Introduction 65 D.

Siegmund J. Baum It has become a tradition to commence advocated by Leonard Cole) (3). important meetings of this society with At about the same time, Alpen and reminiscence and nostalgia. Bone marrow Baum (4), using a larger mammal, the dog, transplantation, which has a history of only demonstrated that injecting autologous marrow 30 to 40 years, permits this process, since post irradiation would protect lethally some of the early investigators are still with irradiated animals (see Table). Certainly, us. For example, over the past 15 years, we protection was obtained from the cellular have had three symposia in honor of Egon constituents of the bone marrow. Lorenz. As we all know, the team of Lorenz, We undertook to test on dogs the Uphoff and Congdon was involved in the first hypothesis of Gengozian and Makinodum (5) that successful transplantation of syngeneic and increasing the radiation dose will increase allogeneic bone marrow into irradiated immunologic tolerance for allogeneic implants.

It is perhaps not too much of an exaggeration to claim that experimental hematology as it flourishes today originated largely from the pioneering attempts to protect lethally radiated animals (1) by shielding of hemopoietic tissues by L. O. Jacobson (9), and (2) by treatment with bone marrow suspensions by E. Lorenz and his col- laborators (12). The site chosen for this annual meeting of the International Society for Experi- mental Hematology is given a special historic sig- nificance by the fact that it was 25 years ago that the first publication on this subject by Lorenz ap- peared from his laboratory at the National Insti- tutes of Health. Lorenz's discovery marked the beginning of a period which lasted until 1956, during which the protection afforded by hemopoietic cell suspensions was confirmed by many. This soon led to an intensive scientific de- bate on the mechanism of this protective effect: was it due to a humoral factor produced and pro- vided by the bone marrow-as Lorenz The Appearance of postulated-or to transplantation and subsequent proliferation of hemop- etic cells?This question was defini- 1 the Multipotential tively answered in 1956 by evidence from three different laboratories (7, 15, 26), which demonstrated the origin of the cells Hemopoietic in the repopulated tissues using a variety of cellu- lar and immunologic markers. By the same token, these contributions marked the birth of radiation Stem Cell chimeras.

Experimental Hematology Today - 1988 presents the latest results of research reflecting the diverse interests of basic and clinical hematologists. The major areas explored are hematopoietic regulation by cytokines; hematopoietic cellular growth regulation, with emphasis on the interaction of stromal with hematopoietic stem and progenitor cells; granulopoietic regulators; gene transfers into hematopoietic progenitor cells; leukemogenesis; and bone marrow transplantation. All chapters report on research or clinical findings of the past year.